Steroids of a common oral contraceptive, "Norinyl", which composed of norethindrone (progestin) and mestranol (estrogen), were fed either singly or in combination to ovariectomized guinea pigs. Ascorbic acid intake was maintained throughout the study at 20 mg/kg body weight/day by allowing the animals to consume the exact amount of vitamin in a 20% sucrose solution from a modified syringe. Steroids were provided in a similar manner and were equal to 18mg norethindrone or 0.91 mg mestranol or both per kg of body weight. A scorbutic practical diet and water were provided and libitum. After 6 weeks of steroid treatment, the guinea pigs were injected intraperitoneally with 2 micron Ci ascorbic acid (U-14C) per 100 g body weight and then placed individually in metabolic chambers where respiratory CO2, urinary and fecal excretion were collected for 72 hours. Then blood was collected by heart puncture and liver, adrenal and spleen were excised. The radioactivity and quantity of ascrobic, dehydroascorbic and diketogulonic acids in the samples were determined by a thin layer chromatographic method. Preliminary data indicate that the pulmonary elimination of 14CO2 as expressed by % injected dose appeared to be slightly higher in mestranol treated guinea pigs. This may explain why blood and tissue ascorbic and levels were reduced in contraceptive treated animals.